Many Australians may not be aware that they have high cholesterol, according to figures released by the Australian Bureau of Statistics (ABS) today.

Dr Paul Jelfs, head of the Social, Health & Labour Division at the ABS, said the results from the groundbreaking biomedical collection in the Australian Health Survey give an important insight into Australia's heart health.

"The blood test results showed that one in three Australian adults, or 5.6 million people, had high total cholesterol levels. Yet only one in every ten people in this group already knew they had it," Dr Jelfs said.

The range of cardiovascular tests in the survey showed that the majority of Australians aged 45 and over were at risk of heart disease.

"The results showed that around three in every four Australians aged 45 and over had risk factors for heart disease. That is, they were either taking cholesterol-lowering medication, or their blood test results showed that they had one or more of high total cholesterol, high 'bad' cholesterol, low 'good' cholesterol or high triglycerides (fats in the blood).

"Interestingly, the picture was not much brighter for younger people, with nearly half of those aged under 45 having at least one of these risk factors," Dr Jelfs said.